With the increasing popularity of the Internet, technologies for creating and delivering web pages to users are continuously being developed and refined. Web pages that have static content can be created relatively easily using Hypertext Markup Language (HTML) to define the content of the pages. However, it is more difficult to create dynamic page content that is based on a user request, system status, or other input. One solution has been to use “servlets,” such as JAVA servlets, to dynamically create web page content. JAVA servlets are JAVA programs that execute at a web server (as opposed to an “applet,” which executes in a web browser) and that receive a HyperText Transfer Protocol (HTTP) request, dynamically generate a response to the request, and communicate the response to the web browser in the form of an HTML file. When using this approach, however, the entire web page (the HTML file) must be created by the servlet. Therefore, if a web page developer wishes to modify the appearance of the web page, the developer must access, edit, and recompile the servlet. This is true even if the developer only wants to change the formatting of the web page and does not want to change the logic of the program and the content that the logic creates.
Certain technologies have begun to be developed to separate the application logic from the appearance of the web page and to allow the appearance of the page to be changed without having to access the logic that creates the content. An example of such technology is the JAVASERVER PAGE (JSP) technology. A JSP file is basically an HTML file that includes additional components that execute application logic to generate content. Using JSP technology, web page developers use HTML or Extensible Markup Language (XML) tags to design and format a web page. In addition to the HTML and XML tags, the JSP file also includes JSP tags and/or scriptlets that generate content in the web page. The application logic that generates the content may be included in JAVA programs, such as JAVABEANS, that are executed at the web server using the JSP tags. The HTML and XML tags are used to format the content produced by the JSP tags and scriptlets, such that the appearance of the page may be changed by modifying the HTML or XML tags without having to modify the underlying JAVA programs that are generating the content.
In addition to the standard JSP tags that are defined in the JSP specification, the current version of JSP allows for the use of custom tags. Custom tags give the web page developer even greater flexibility in the design of web pages. Although custom JAVA code may be included in JSP files as scriptlets that create content, custom tags can be used to create this same content by executing separate JAVA applications. Therefore, instead of having to include JAVA code in the JSP file, the developer only has to include a custom tag and a minimal amount of supporting code. The use of custom tags allows for the further separation of the content generation and page formatting tasks of developing a web page. Unfortunately, custom tags have not been available in previous version of JSP, and developers using these earlier versions have not been able to take advantage of custom tags.